Is there a role for short-term hormone use in the treatment of nonmetastatic prostate cancer?

Abstract

We reviewed our institution's experience treating patients with prostate cancer with 3-dimensional conformal radiation therapy (3DCRT) and short-term adjuvant hormonal therapy to determine biochemical no evidence of disease (bNED) and clinical outcome compared with patients treated with 3DCRT alone. Between 4/1/89 and 11/30/94, 558 patients with clinically localized prostate cancer received treatment at Fox Chase Cancer Center (Philadelphia, Pa.); 484 patients were treated with 3DCRT alone (Group I); 74 patients were treated with 3DCRT and hormones (Group II). Five-year actuarial rates of bNED control, distant metastasis-free survival (DMFS), cause-specific survival (CSS), and overall survival (OS) were calculated for pretreatment PSA, Gleason score, T stage, use of hormones, treatment field size, age, and dose. A matched case/control analysis was performed to further evaluate the effect of hormones on treatment with 3DCRT. Median follow-up was 47 months (range: 2-97 months). The 5-year actuarial rates of bNED control, DMFS, CSS, and OS were 66%, 93%, 98%, and 86%, respectively, for Group I patients and 68%, 93%, 98%, and 89%, respectively, for Group II patients. Multivariate analysis demonstrated that hormone use was an independent predictor of bNED control only. A significant difference in bNED control was observed between Group I and II (43% vs. 71%) using the matched case/control analysis (P = 0.02). A trend towards significance was observed for different rates of DMFS between Group I and II (79% vs. 94%, P = 0.09). Patients with clinically localized prostate cancer with poor prognostic features (pretreatment PSA > or = 10 ng/ml, Gleason score > or = 7, and/or T2c or greater palpation stage) show improved rates of bNED control and a trend towards improved DMFS when treated with 3DCRT and short-term adjuvant hormones compared with 3DCRT alone. Long-term observation will be necessary to see if improvements in bNED control will translate into improvements in overall survival.